Electroproduction of the Φ(1020) Vector Meson at 4 GeV

Thesis/Dissertation · Tue Feb 01 04:00:00 EST 2000

DOI:https://doi.org/10.2172/824905· OSTI ID:824905

Loukachine, Konstantin ^[1]

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1. Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

We studied the reaction ep → e'p'Φ with a 4.2 GeV incident electron beam in the region of the electroproduction variables Q² from 0.7 to 2.2 GeV² and W from 2.0 to 2.6 GeV. The data were taken and analyzed at the Thomas Jefferson National Accelerator Facility. For the first time, we observe the expected t-slope dependence on Q² and Δτ in Φ vector meson production. We find that the width of the forward Φ-meson diffraction peak increases rapidly as the interaction time decreases below cΔτ of 1 fm. Within a simple optical model framework, the data show that Φ meson has a smaller size than the ρ. The measured Φ cross-section dependence on Q² is in a good agreement with previous measurements and well-described by the phenomenological Pomeron exchange model. Our cross-section data do not favor the standard Vector Meson Dominance and s$$\bar{s}$$-knockout model predictions. From the angular distribution of the decay Φ → K⁺ K^-, assuming the s-channel helicity conservation, we extracted the longitudinal-to-transverse cross-section ratio, R, and Vector Meson Dominance scaling parameter, ζ², which are consistent with the previous measurements and the model expectations.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Energy Research (ER)
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 824905
• Report Number(s): JLAB-PHY--00-68; DOE/ER/40150--2751
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ANGULAR DISTRIBUTION
CEBAF ACCELERATOR
DECAY
DIFFRACTION
ELECTRON BEAMS
ELECTROPRODUCTION
HELICITY
MESONS
OPTICAL MODELS
PERIPHERAL MODELS
POMERANCHUK PARTICLES
PRODUCTION
S CHANNEL
VECTOR MESONS